The atopy patch test -- reproducibility and comparison of different evaluation methods

BACKGROUND: There is still a lack of standardization of the atopy patch test (APT) in test procedures and evaluation methods. Our aim was to examine the reproducibility of APT results and to compare visual evaluation to chromametry and laser Doppler imaging. METHODS: Fifty-two volunteers with atopic eczema/dermatitis syndrome (AEDS) were included. The APT was performed on tape-stripped and unstripped test fields on their backs using cat dander, house dust mite and grass pollen allergens from two different suppliers. Responders were re-tested 4-12 weeks later with the same allergens on their forearms. RESULTS: Using Allergopharma allergens, 14 (26.9%) volunteers showed one or more positive reactions. The reproducibility rate was 56.3%. The Erlangen atopy score in APT-positive and negative volunteers was 19 +/- 6 vs 15 +/- 6. The test agreement in volunteers tested with both allergens, from Allergopharma and Stallergènes, was poor. Correlation of the results between the three evaluation methods was significant (P < or = 0.001). CONCLUSIONS: The low reproducibility rate of APT results and the poor inter-test-agreement using allergens from different suppliers show that much work remains to make the APT a reliable tool in identifying relevant aeroallergens that lead to flare ups of AEDS. Compared to chromametry and laser Doppler imaging, visual scoring was superior in differentiation between irritative and allergic reactions.     

Investigation and improved performance of optical fibre probes in laser Doppler blood flow measurement

Laser Doppler flowmetry with optical-fibre beam transmission is a sensitive fast and convenient method of measuring tissue blood flow. However, its sensitivity can also be a problem because of movement artefacts. This study applies some basic considerations of fibre optics and Rayleigh light scattering to the field of laser Doppler blood flow meters. Practical suggestions are given by which movement arterfacts can be reduced by choice of optical fibres, attention to probe geometry, cladding the fibres to reduce their movements and in the method of application. Experiments which test the normalisation circuitry of laser Doppler instruments are described and the effects of movement artefacts on the interpretation of the pulsatile component of laser Doppler records are also discussed. Probe and fibre line movements cause high-frequency intensity fluctuations due to speckle movement. The intensity fluctuations produce an apparent Doppler shift much greater than the Doppler shift produced by the relative movements of probe and tissue. It has been found that it is important to ensure that the fields of view of the illuminating and detecting fibres do not overlap at the skin surface and that probe contact with the skin surface should be maintained.     

癫癎患者脑血流速度改变与癫癎灶定侧的关系

目的 :探讨癫发作间期脑血流变化对癫灶定侧的价值。方法 :4 7例癫病人发作间期行经颅多普勒超声脑血流速度测定 ,并与临床、脑电图定位和MRI/CT病灶对比分析。结果 :根据临床症状确定病灶侧的 19例病人中 ,病灶侧脑血流速度改变 (升高和降低 )的比率显著高于双侧脑血流速度对称者 ;在脑电图确定病灶侧的 2 4例病人中 ,病灶侧脑血流速度升高比率显著高于脑血流速度降低和双侧脑血流速度对称者 ;在MRI确定病灶侧的 13例病人中 ,病灶侧脑血流速度增快 7例 ,减慢 2例 ,双侧血流速度对称 4例。结论 :癫病人一侧脑血流速度增高 ,高度提示癫病灶侧。     

应用激光电泳技术对MA737小鼠乳腺癌细胞膜表面电荷特性的研究

本工作应用激光多普勒电泳技术对ＭＡ７３７小鼠乳腺癌细胞膜表面电荷特性及高温（４２．５℃）对癌细胞的热效应进行了深入的研究。结果发现，ＭＡ７３７癌细胞的电泳迁移率（ＥＰＭ）明显高于相应正常细胞的ＥＰＭ（约２０％），表明癌细胞表面负电荷增高；实验发现唾液酸可能是ＭＡ７３７癌细胞膜表主要负电基团的来源之一。研究还发现，ＭＡ７３７癌细胞的热敏性比相应的正常细胞强，随高温受热时间的延长，癌细胞的ＥＰＭ呈下降趋势。     

Parameters and standardization in obstetric Doppler

Obstetric Doppler is still largely empirically based, although possible clinical applications are already under examination. This article examines some of the basic instrumentation and hemodynamic issues — which physiological parameters would we ideally like to assess, and what can we do in practice with current Doppler instrumentation? It is shown that the rate of blood flow and the flow resistance are two of the most basic hemodynamic parameters. It is possible to estimate the flow rate with (specialized) Doppler equipment, but there is no method available at present to measure the flow resistance. Analysis of the blood velocity waveform provides some information concerning flow resistance, as long as it can be assumed that other factors that might affect the waveform have not deviated significantly from the norm. Practical considerations in choosing the instrumentation and designing the examination protocol are discussed, and issues of quality control are emphasized.     

偏头痛患儿的大脑血流动力学变化

目的　研究偏头痛患儿的脑动脉血流动力学改变 ,探讨其在小儿偏头痛发生中的作用。方法　应用经颅多普勒 (TCD)技术 ,检测 90例 7～ 14岁头痛间歇期的偏头痛患儿和 80例健康同龄儿童脑动脉血管血流动力学指标。结果　 90例偏头痛患儿中脑动脉血流动力学异常者 77例 (86 % ) ,其中 6 0例 (6 7% )流速增快 ,9例 (10 % )减慢 ,与对照组相比 ,差异具有显著性 (P <0 0 1) ;90例中 2 3例 (2 6 % )存在双侧同名动脉血流速度不对称 ,其中伴有血流速度异常者15例 ,血流速度正常者 8例 ,差异具有显著性 (P <0 0 1)。结论　脑动脉血流动力学因素异常改变 ,在小儿偏头痛的发生中具有重要作用。尤其值得注意的是 ,双侧同名动脉流速不对称的改变 ,在小儿偏头痛的发生中同样可能起着重要的作用。     

多普勒组织显像评价高血压病心房内传导间期变化与房性心律失常的关系

目的　应用多普勒组织显像评价高血压病心房内传导间期变化与房性心律失常的关系 ;方法　利用超声多普勒组织显像法测量了 2 0例高血压病心房内传导间期与正常人对比分析 ;结果　高血压病心房内传导间期存在异常 ,心房内传导间期与左房内径大小无相关 (r =0 1,P >0 2 5 ) ,与左室舒张功能指标E A比值中度相关 (r=0 5 7,0 0 1

0 2 5 ) ;结论　高血压病房性心律失常与心房内传导异常及左室舒张功能有关 ,多普勒组织显像法是一种较好的测量高血压病心房内传导间期的方法     

120例典型偏头痛发作期的经颅多普勒观察

目的：探讨典型偏头痛发作期的脑血流动力学变化。方法：应用经颅多普勒（ＴＣＤ）对１２０例典型偏头痛患发作期进行观察。结果：平均血流速度（Ｖｍ）加快７０例（５８．３％）与对照组比较有非常显差异（Ｐ〈０．０１）;Ｖｍ减慢３８例（３１．７％）,与对照组比较有显差异（Ｐ〈０．０５）;Ｖｍ正常１２例（１０％）。结论：应用ＴＣＤ对典型偏头痛的检查,有助于诊断和指导治疗,亦有助于对偏头痛发生机理的研究。     

Influence of left ventricular filling proffle during preceding control beats on pulse pressure during ventricular premature contractions

We investigated whether the left ventricular filling profile,defined as the early to late diastolic left ventricular fillingvolume ratio, during the preceding control beats actually affectsthe pulse pressure during a ventricular premature contraction(PVC). Twenty patients underwent invasive electrophysiologicalstudy for sinus bradycardia. VPCs with various coupling intervalswere induced by right ventricular electrical stimulation, andthe mitral filling flow velocity pulsed Doppler echocardiography,the femoral arterial pressure curve and the electrocardiogramwere simultaneously recorded The early to late diastolic velocity-rimeintegral ratio (E₁/A₁ ratio) of the mitral filling flow velocityduring the control beats which preceded the VPC was measuredas an index characterizing left ventricular filling profile.The coupling interval of each VPC and the extrasystolic beatpulse pressure were measured The ratio of the extrasystolicbeat pulse pressure to the control beat pulse pressure was expressedin % (% extrasystolic beat pulse pressure). The correlationbetween the coupling interval and the % extrasystolic beat pulsepressure was investigated. Coupling intervals of 0·80,0·70, 0·60, 0·50, and 0·45 s wereused At a coupling interval of 0·80 or 0·45 s,the % extrasystolic beat pulse pressure showed no significantcorrelation with the E₁/A₁ ratio. In contrast, the % extrasystolicbeat pulse pressure with coupling intervals of 0·70,0·60, and 0·50 s showed a significant positivecorrelation with the E₁/A₁ ratio (r=0·67, 0·74,and 0·66 P<0·01, respectively). In additionto the prematurity and the site of origin of the VPCs, the leftventricular filling profile during the preceding control beatsmay significantly affect the height of the pulse pressure duringextrasystoles with medium length coupling intervals.     

Transcranial Doppler sonography in craniosynostosis

In the management of craniosynostosis, there is a need for quantitative assessment of treatment methods and outcome. Radiology and pressure studies are well documented, but so far little attention has been given to cerebral blood flow changes and their possible relevance. This paper reports our initial experience using transcranial Doppler sonography to calculate the cerebrovascular resistance and cerebral blood velocities in the major basal vessels before and after surgery for craniosynostosis. Ten patients were studied using the Scimed 2-MHz probe through the temporal and frontal windows of the skull. Measurements were taken under standard physiological conditions before, during and after surgery. Preliminary results suggest that this non-invasive technique may be helpful in predicting and assessing the outcome following surgery for craniosynostosis.